Dar es Salaam , Tanzania -LRB- CNN -RRB- -- An estimated 3 billion people -- nearly half the world 's population -- still use an open fire as their primary source of energy for cooking and heating .

But there 's a problem : the smoke .

`` You have respiratory issues , lung disease , you 've got pneumonia , and you 've got longer-term issues like cancer and heart disease as well that can result from exposure to indoor air pollution , '' said Radha Muthiah , executive director of the Global Alliance for Clean Cookstoves .

The World Health Organization says this type of pollution causes nearly 2 million premature deaths each year . That 's more than tuberculosis and three times as many as malaria .

Everline Kihulla is among the people trying to do something about it . She works for TaTedo , which manufactures and sells `` clean cookstoves '' in Tanzania .

TaTedo 's stoves are made with clay liners that , along with other simple design features , emit far less smoke and fewer pollutants . And they use a fraction of the fuel .

`` This -LRB- stove -RRB- , we have improved it , and it currently uses almost 50 % , compared to the traditional one , '' she said , crouching beside one of TaTedo 's models . `` The charcoal consumption here is less , compared to the traditional one . ''

Another benefit is that these stoves are made locally . A nearby workshop employs 21 people and churns out 400 to 500 stoves each month . Each person follows a cookstove through every stage of production , from pottery to painting . This teaches each worker a variety of skills .

Producing locally also boosts the economy and keeps costs down , although price is an issue . Cookstove prices start at about $ 6 -LRB- U.S. -RRB- , a lot of money for many families in developing countries .

Still , Lillian Njuu , a Dar es Salaam resident , thinks the expense is worth the health of her family . She has used a clean stove for two years , she said , and she plans to buy another .

While the upfront cost to buy a cookstove is high , the fuel costs are lower because it burns less . That , in turn , has an environmental impact . Burning less charcoal or wood means there 's less deforestation , something that has caused flooding and other major problems in many countries .

`` It 's one relatively simple intervention that has a multitude of impacts , '' Muthiah said .

Now , the challenge is to get clean stoves into enough homes to really make a difference .

David Lindsay is the managing editor of Global Health Frontline News . For more global health stories , go to www.ghfn.org .

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Worldwide , nearly 2 million premature deaths each year are linked to indoor smoke

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The smoke comes when people use an open fire to cook or heat their homes , a common practice

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In Tanzania , they 're producing `` clean cookstoves '' that emit far less smoke , fewer pollutants